MINOR: http: add new function http_path_has_forbidden_char()

Origin: https://git.haproxy.org/?p=haproxy-2.2.git;a=commit;h=921f79588c6180c406e88236228a5be1c5c67c55

As its name implies, this function checks if a path component has any
forbidden headers starting at the designated location. The goal is to
seek from the result of a successful ist_find_range() for more precise
chars. Here we're focusing on 0x00-0x1F, 0x20 and 0x23 to make sure
we're not too strict at this point.

(cherry picked from commit 30f58f4217d585efeac3d85cb1b695ba53b7760b)
 [ad: backported for following fix : BUG/MINOR: h2: reject more chars
  from the :path pseudo header]
Signed-off-by: Amaury Denoyelle <adenoyelle@haproxy.com>
(cherry picked from commit b491940181a88bb6c69ab2afc24b93a50adfa67c)
Signed-off-by: Amaury Denoyelle <adenoyelle@haproxy.com>
(cherry picked from commit f7666e5e43ce63e804ebffdf224d92cfd3367282)
Signed-off-by: Amaury Denoyelle <adenoyelle@haproxy.com>
(cherry picked from commit c699bb17b7e334c9d56e829422e29e5a204615ec)
[wt: adj minor ctx in http.h]
Signed-off-by: Willy Tarreau <w@1wt.eu>
(cherry picked from commit 0f57ac20b046b70275192651d7b6c978032e6a36)
[wt: adj minor ctx in http.h]
Signed-off-by: Willy Tarreau <w@1wt.eu>
Gbp-Pq: Name MINOR-http-add-new-function-http_path_has_forbidden_.patch

diff --git a/include/haproxy/http.h b/include/haproxy/http.h
index 00a64c7b7d3624414eda7b40129b8c2a539e059b..34987c2b5c8f99d7f75215dacdf3dffdf1e082f3 100644 (file)
--- a/include/haproxy/http.h
+++ b/include/haproxy/http.h
@@ -105,6 +105,25 @@ static inline int http_language_range_match(const char *range, int range_len,
        return tag == tend;
 }
 
+/* Looks into <ist> for forbidden characters for :path values (0x00..0x1F,
+ * 0x20, 0x23), starting at pointer <start> which must be within <ist>.
+ * Returns non-zero if such a character is found, 0 otherwise. When run on
+ * unlikely header match, it's recommended to first check for the presence
+ * of control chars using ist_find_ctl().
+ */
+static inline int http_path_has_forbidden_char(const struct ist ist, const char *start)
+{
+       do {
+               if ((uint8_t)*start <= 0x23) {
+                       if ((uint8_t)*start < 0x20)
+                               return 1;
+                       if ((1U << ((uint8_t)*start & 0x1F)) & ((1<<3) | (1<<0)))
+                               return 1;
+               }
+               start++;
+       } while (start < istend(ist));
+       return 0;
+}
 
 #endif /* _HAPROXY_HTTP_H */